[Downloads UI] Implement search

chrome/android/java/src/org/chromium/chrome/browser/download/ui/BackendItems.java

Index: chrome/android/java/src/org/chromium/chrome/browser/download/ui/BackendItems.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/download/ui/BackendItems.java b/chrome/android/java/src/org/chromium/chrome/browser/download/ui/BackendItems.java
index 18d6b1a26521fc550a64882634e5c962520d5c1b..eea1dee37f5438d832ba5a8e00065a3c3b9cf30f 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/download/ui/BackendItems.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/download/ui/BackendItems.java
@@ -7,6 +7,7 @@ package org.chromium.chrome.browser.download.ui;
 import android.text.TextUtils;
 
 import java.util.ArrayList;
+import java.util.Locale;
 
 /**
  * Stores a List of DownloadHistoryItemWrappers for a particular download backend.
@@ -32,7 +33,6 @@ public abstract class BackendItems extends ArrayList<DownloadHistoryItemWrapper>
 
     /**
      * Filters out items that are displayed in this list for the current filter.
-     * TODO(dfalcantara): Show all non-cancelled downloads.
      *
      * @param filterType    Filter to use.
      * @param filteredItems List for appending items that match the filter.
@@ -44,6 +44,24 @@ public abstract class BackendItems extends ArrayList<DownloadHistoryItemWrapper>
     }
 
     /**
+     * Filters out items that match the query and are displayed in this list for the current filter.
+     * @param filterType    Filter to use.
+     * @param query         The text to match.
+     * @param filteredItems List for appending items that match the filter.
+     */
+    public void filter(int filterType, String query, BackendItems filteredItems) {
+        for (DownloadHistoryItemWrapper item : this) {
+            query = query.toLowerCase(Locale.getDefault());
+            Locale locale = Locale.getDefault();
+            if (item.isVisibleToUser(filterType)
+                    && (item.getDisplayHostname().toLowerCase(locale).contains(query)
+                    || item.getDisplayFileName().toLowerCase(locale).contains(query))) {
+                filteredItems.add(item);
+            }
+        }
+    }
+
+    /**
      * Search for an existing entry with the given ID.
      * @param guid GUID of the entry.
      * @return The index of the item, or INVALID_INDEX if it couldn't be found.